﻿/*
 * FCKeditor - The text editor for Internet - http://www.fckeditor.net
 * Copyright (C) 2003-2009 Frederico Caldeira Knabben
 *
 * == BEGIN LICENSE ==
 *
 * Licensed under the terms of any of the following licenses at your
 * choice:
 *
 *  - GNU General Public License Version 2 or later (the "GPL")
 *    http://www.gnu.org/licenses/gpl.html
 *
 *  - GNU Lesser General Public License Version 2.1 or later (the "LGPL")
 *    http://www.gnu.org/licenses/lgpl.html
 *
 *  - Mozilla Public License Version 1.1 or later (the "MPL")
 *    http://www.mozilla.org/MPL/MPL-1.1.html
 *
 * == END LICENSE ==
 *
 * Controls the [Enter] keystroke behavior in a document.
 */

/*
 *    Constructor.
 *        @targetDocument : the target document.
 *        @enterMode : the behavior for the <Enter> keystroke.
 *            May be "p", "div", "br". Default is "p".
 *        @shiftEnterMode : the behavior for the <Shift>+<Enter> keystroke.
 *            May be "p", "div", "br". Defaults to "br".
 */
var FCKEnterKey = function( targetWindow, enterMode, shiftEnterMode, tabSpaces )
{
    this.Window            = targetWindow ;
    this.EnterMode        = enterMode || 'p' ;
    this.ShiftEnterMode    = shiftEnterMode || 'br' ;

    // Setup the Keystroke Handler.
    var oKeystrokeHandler = new FCKKeystrokeHandler( false ) ;
    oKeystrokeHandler._EnterKey = this ;
    oKeystrokeHandler.OnKeystroke = FCKEnterKey_OnKeystroke ;

    oKeystrokeHandler.SetKeystrokes( [
        [ 13        , 'Enter' ],
        [ SHIFT + 13, 'ShiftEnter' ],
        [ 8            , 'Backspace' ],
        [ CTRL + 8    , 'CtrlBackspace' ],
        [ 46        , 'Delete' ]
    ] ) ;

    this.TabText = '' ;

    // Safari by default inserts 4 spaces on TAB, while others make the editor
    // loose focus. So, we need to handle it here to not include those spaces.
    if ( tabSpaces > 0 || FCKBrowserInfo.IsSafari )
    {
        while ( tabSpaces-- )
            this.TabText += '\xa0' ;

        oKeystrokeHandler.SetKeystrokes( [ 9, 'Tab' ] );
    }

    oKeystrokeHandler.AttachToElement( targetWindow.document ) ;
}


function FCKEnterKey_OnKeystroke(  keyCombination, keystrokeValue )
{
    var oEnterKey = this._EnterKey ;

    try
    {
        switch ( keystrokeValue )
        {
            case 'Enter' :
                return oEnterKey.DoEnter() ;
                break ;
            case 'ShiftEnter' :
                return oEnterKey.DoShiftEnter() ;
                break ;
            case 'Backspace' :
                return oEnterKey.DoBackspace() ;
                break ;
            case 'Delete' :
                return oEnterKey.DoDelete() ;
                break ;
            case 'Tab' :
                return oEnterKey.DoTab() ;
                break ;
            case 'CtrlBackspace' :
                return oEnterKey.DoCtrlBackspace() ;
                break ;
        }
    }
    catch (e)
    {
        // If for any reason we are not able to handle it, go
        // ahead with the browser default behavior.
    }

    return false ;
}

/*
 * Executes the <Enter> key behavior.
 */
FCKEnterKey.prototype.DoEnter = function( mode, hasShift )
{
    // Save an undo snapshot before doing anything
    FCKUndo.SaveUndoStep() ;

    this._HasShift = ( hasShift === true ) ;

    var parentElement = FCKSelection.GetParentElement() ;
    var parentPath = new FCKElementPath( parentElement ) ;
    var sMode = mode || this.EnterMode ;

    if ( sMode == 'br' || parentPath.Block && parentPath.Block.tagName.toLowerCase() == 'pre' )
        return this._ExecuteEnterBr() ;
    else
        return this._ExecuteEnterBlock( sMode ) ;
}

/*
 * Executes the <Shift>+<Enter> key behavior.
 */
FCKEnterKey.prototype.DoShiftEnter = function()
{
    return this.DoEnter( this.ShiftEnterMode, true ) ;
}

/*
 * Executes the <Backspace> key behavior.
 */
FCKEnterKey.prototype.DoBackspace = function()
{
    var bCustom = false ;

    // Get the current selection.
    var oRange = new FCKDomRange( this.Window ) ;
    oRange.MoveToSelection() ;

    // Kludge for #247
    if ( FCKBrowserInfo.IsIE && this._CheckIsAllContentsIncluded( oRange, this.Window.document.body ) )
    {
        this._FixIESelectAllBug( oRange ) ;
        return true ;
    }

    var isCollapsed = oRange.CheckIsCollapsed() ;

    if ( !isCollapsed )
    {
        // Bug #327, Backspace with an img selection would activate the default action in IE.
        // Let's override that with our logic here.
        if ( FCKBrowserInfo.IsIE && this.Window.document.selection.type.toLowerCase() == "control" )
        {
            var controls = this.Window.document.selection.createRange() ;
            for ( var i = controls.length - 1 ; i >= 0 ; i-- )
            {
                var el = controls.item( i ) ;
                el.parentNode.removeChild( el ) ;
            }
            return true ;
        }

        return false ;
    }

    // On IE, it is better for us handle the deletion if the caret is preceeded
    // by a <br> (#1383).
    if ( FCKBrowserInfo.IsIE )
    {
        var previousElement = FCKDomTools.GetPreviousSourceElement( oRange.StartNode, true ) ;

        if ( previousElement && previousElement.nodeName.toLowerCase() == 'br' )
        {
            // Create a range that starts after the <br> and ends at the
            // current range position.
            var testRange = oRange.Clone() ;
            testRange.SetStart( previousElement, 4 ) ;

            // If that range is empty, we can proceed cleaning that <br> manually.
            if ( testRange.CheckIsEmpty() )
            {
                previousElement.parentNode.removeChild( previousElement ) ;
                return true ;
            }
        }
    }

    var oStartBlock = oRange.StartBlock ;
    var oEndBlock = oRange.EndBlock ;

    // The selection boundaries must be in the same "block limit" element
    if ( oRange.StartBlockLimit == oRange.EndBlockLimit && oStartBlock && oEndBlock )
    {
        if ( !isCollapsed )
        {
            var bEndOfBlock = oRange.CheckEndOfBlock() ;

            oRange.DeleteContents() ;

            if ( oStartBlock != oEndBlock )
            {
                oRange.SetStart(oEndBlock,1) ;
                oRange.SetEnd(oEndBlock,1) ;

//                if ( bEndOfBlock )
//                    oEndBlock.parentNode.removeChild( oEndBlock ) ;
            }

            oRange.Select() ;

            bCustom = ( oStartBlock == oEndBlock ) ;
        }

        if ( oRange.CheckStartOfBlock() )
        {
            var oCurrentBlock = oRange.StartBlock ;

            var ePrevious = FCKDomTools.GetPreviousSourceElement( oCurrentBlock, true, [ 'BODY', oRange.StartBlockLimit.nodeName ], ['UL','OL'] ) ;

            bCustom = this._ExecuteBackspace( oRange, ePrevious, oCurrentBlock ) ;
        }
        else if ( FCKBrowserInfo.IsGeckoLike )
        {
            // Firefox and Opera (#1095) loose the selection when executing
            // CheckStartOfBlock, so we must reselect.
            oRange.Select() ;
        }
    }

    oRange.Release() ;
    return bCustom ;
}

FCKEnterKey.prototype.DoCtrlBackspace = function()
{
    FCKUndo.SaveUndoStep() ;
    var oRange = new FCKDomRange( this.Window ) ;
    oRange.MoveToSelection() ;
    if ( FCKBrowserInfo.IsIE && this._CheckIsAllContentsIncluded( oRange, this.Window.document.body ) )
    {
        this._FixIESelectAllBug( oRange ) ;
        return true ;
    }
    return false ;
}

FCKEnterKey.prototype._ExecuteBackspace = function( range, previous, currentBlock )
{
    var bCustom = false ;

    // We could be in a nested LI.
    if ( !previous && currentBlock && currentBlock.nodeName.IEquals( 'LI' ) && currentBlock.parentNode.parentNode.nodeName.IEquals( 'LI' ) )
    {
        this._OutdentWithSelection( currentBlock, range ) ;
        return true ;
    }

    if ( previous && previous.nodeName.IEquals( 'LI' ) )
    {
        var oNestedList = FCKDomTools.GetLastChild( previous, ['UL','OL'] ) ;

        while ( oNestedList )
        {
            previous = FCKDomTools.GetLastChild( oNestedList, 'LI' ) ;
            oNestedList = FCKDomTools.GetLastChild( previous, ['UL','OL'] ) ;
        }
    }

    if ( previous && currentBlock )
    {
        // If we are in a LI, and the previous block is not an LI, we must outdent it.
        if ( currentBlock.nodeName.IEquals( 'LI' ) && !previous.nodeName.IEquals( 'LI' ) )
        {
            this._OutdentWithSelection( currentBlock, range ) ;
            return true ;
        }

        // Take a reference to the parent for post processing cleanup.
        var oCurrentParent = currentBlock.parentNode ;

        var sPreviousName = previous.nodeName.toLowerCase() ;
        if ( FCKListsLib.EmptyElements[ sPreviousName ] != null || sPreviousName == 'table' )
        {
            FCKDomTools.RemoveNode( previous ) ;
            bCustom = true ;
        }
        else
        {
            // Remove the current block.
            FCKDomTools.RemoveNode( currentBlock ) ;

            // Remove any empty tag left by the block removal.
            while ( oCurrentParent.innerHTML.Trim().length == 0 )
            {
                var oParent = oCurrentParent.parentNode ;
                oParent.removeChild( oCurrentParent ) ;
                oCurrentParent = oParent ;
            }

            // Cleanup the previous and the current elements.
            FCKDomTools.LTrimNode( currentBlock ) ;
            FCKDomTools.RTrimNode( previous ) ;

            // Append a space to the previous.
            // Maybe it is not always desirable...
            // previous.appendChild( this.Window.document.createTextNode( ' ' ) ) ;

            // Set the range to the end of the previous element and bookmark it.
            range.SetStart( previous, 2, true ) ;
            range.Collapse( true ) ;
            var oBookmark = range.CreateBookmark( true ) ;

            // Move the contents of the block to the previous element and delete it.
            // But for some block types (e.g. table), moving the children to the previous block makes no sense.
            // So a check is needed. (See #1081)
            if ( ! currentBlock.tagName.IEquals( [ 'TABLE' ] ) )
                FCKDomTools.MoveChildren( currentBlock, previous ) ;

            // Place the selection at the bookmark.
            range.SelectBookmark( oBookmark ) ;

            bCustom = true ;
        }
    }

    return bCustom ;
}

/*
 * Executes the <Delete> key behavior.
 */
FCKEnterKey.prototype.DoDelete = function()
{
    // Save an undo snapshot before doing anything
    // This is to conform with the behavior seen in MS Word
    FCKUndo.SaveUndoStep() ;

    // The <Delete> has the same effect as the <Backspace>, so we have the same
    // results if we just move to the next block and apply the same <Backspace> logic.

    var bCustom = false ;

    // Get the current selection.
    var oRange = new FCKDomRange( this.Window ) ;
    oRange.MoveToSelection() ;

    // Kludge for #247
    if ( FCKBrowserInfo.IsIE && this._CheckIsAllContentsIncluded( oRange, this.Window.document.body ) )
    {
        this._FixIESelectAllBug( oRange ) ;
        return true ;
    }

    // There is just one special case for collapsed selections at the end of a block.
    if ( oRange.CheckIsCollapsed() && oRange.CheckEndOfBlock( FCKBrowserInfo.IsGeckoLike ) )
    {
        var oCurrentBlock = oRange.StartBlock ;
        var eCurrentCell = FCKTools.GetElementAscensor( oCurrentBlock, 'td' );

        var eNext = FCKDomTools.GetNextSourceElement( oCurrentBlock, true, [ oRange.StartBlockLimit.nodeName ],
                ['UL','OL','TR'], true ) ;

        // Bug #1323 : if we're in a table cell, and the next node belongs to a different cell, then don't
        // delete anything.
        if ( eCurrentCell )
        {
            var eNextCell = FCKTools.GetElementAscensor( eNext, 'td' );
            if ( eNextCell != eCurrentCell )
                return true ;
        }

        bCustom = this._ExecuteBackspace( oRange, oCurrentBlock, eNext ) ;
    }

    oRange.Release() ;
    return bCustom ;
}

/*
 * Executes the <Tab> key behavior.
 */
FCKEnterKey.prototype.DoTab = function()
{
    var oRange = new FCKDomRange( this.Window );
    oRange.MoveToSelection() ;

    // If the user pressed <tab> inside a table, we should give him the default behavior ( moving between cells )
    // instead of giving him more non-breaking spaces. (Bug #973)
    var node = oRange._Range.startContainer ;
    while ( node )
    {
        if ( node.nodeType == 1 )
        {
            var tagName = node.tagName.toLowerCase() ;
            if ( tagName == "tr" || tagName == "td" || tagName == "th" || tagName == "tbody" || tagName == "table" )
                return false ;
            else
                break ;
        }
        node = node.parentNode ;
    }

    if ( this.TabText )
    {
        oRange.DeleteContents() ;
        oRange.InsertNode( this.Window.document.createTextNode( this.TabText ) ) ;
        oRange.Collapse( false ) ;
        oRange.Select() ;
    }
    return true ;
}

FCKEnterKey.prototype._ExecuteEnterBlock = function( blockTag, range )
{
    // Get the current selection.
    var oRange = range || new FCKDomRange( this.Window ) ;

    var oSplitInfo = oRange.SplitBlock( blockTag ) ;

    if ( oSplitInfo )
    {
        // Get the current blocks.
        var ePreviousBlock    = oSplitInfo.PreviousBlock ;
        var eNextBlock        = oSplitInfo.NextBlock ;

        var bIsStartOfBlock    = oSplitInfo.WasStartOfBlock ;
        var bIsEndOfBlock    = oSplitInfo.WasEndOfBlock ;

        // If there is one block under a list item, modify the split so that the list item gets split as well. (Bug #1647)
        if ( eNextBlock )
        {
            if ( eNextBlock.parentNode.nodeName.IEquals( 'li' ) )
            {
                FCKDomTools.BreakParent( eNextBlock, eNextBlock.parentNode ) ;
                FCKDomTools.MoveNode( eNextBlock, eNextBlock.nextSibling, true ) ;
            }
        }
        else if ( ePreviousBlock && ePreviousBlock.parentNode.nodeName.IEquals( 'li' ) )
        {
            FCKDomTools.BreakParent( ePreviousBlock, ePreviousBlock.parentNode ) ;
            oRange.MoveToElementEditStart( ePreviousBlock.nextSibling );
            FCKDomTools.MoveNode( ePreviousBlock, ePreviousBlock.previousSibling ) ;
        }

        // If we have both the previous and next blocks, it means that the
        // boundaries were on separated blocks, or none of them where on the
        // block limits (start/end).
        if ( !bIsStartOfBlock && !bIsEndOfBlock )
        {
            // If the next block is an <li> with another list tree as the first child
            // We'll need to append a placeholder or the list item wouldn't be editable. (Bug #1420)
            if ( eNextBlock.nodeName.IEquals( 'li' ) && eNextBlock.firstChild
                    && eNextBlock.firstChild.nodeName.IEquals( ['ul', 'ol'] ) )
                eNextBlock.insertBefore( FCKTools.GetElementDocument( eNextBlock ).createTextNode( '\xa0' ), eNextBlock.firstChild ) ;
            // Move the selection to the end block.
            if ( eNextBlock )
                oRange.MoveToElementEditStart( eNextBlock ) ;
        }
        else
        {
            if ( bIsStartOfBlock && bIsEndOfBlock && ePreviousBlock.tagName.toUpperCase() == 'LI' )
            {
                oRange.MoveToElementStart( ePreviousBlock ) ;
                this._OutdentWithSelection( ePreviousBlock, oRange ) ;
                oRange.Release() ;
                return true ;
            }

            var eNewBlock ;

            if ( ePreviousBlock )
            {
                var sPreviousBlockTag = ePreviousBlock.tagName.toUpperCase() ;

                // If is a header tag, or we are in a Shift+Enter (#77),
                // create a new block element (later in the code).
                if ( !this._HasShift && !(/^H[1-6]$/).test( sPreviousBlockTag ) )
                {
                    // Otherwise, duplicate the previous block.
                    eNewBlock = FCKDomTools.CloneElement( ePreviousBlock ) ;
                }
            }
            else if ( eNextBlock )
                eNewBlock = FCKDomTools.CloneElement( eNextBlock ) ;

            if ( !eNewBlock )
                eNewBlock = this.Window.document.createElement( blockTag ) ;

            // Recreate the inline elements tree, which was available
            // before the hitting enter, so the same styles will be
            // available in the new block.
            var elementPath = oSplitInfo.ElementPath ;
            if ( elementPath )
            {
                for ( var i = 0, len = elementPath.Elements.length ; i < len ; i++ )
                {
                    var element = elementPath.Elements[i] ;

                    if ( element == elementPath.Block || element == elementPath.BlockLimit )
                        break ;

                    if ( FCKListsLib.InlineChildReqElements[ element.nodeName.toLowerCase() ] )
                    {
                        element = FCKDomTools.CloneElement( element ) ;
                        FCKDomTools.MoveChildren( eNewBlock, element ) ;
                        eNewBlock.appendChild( element ) ;
                    }
                }
            }

            if ( FCKBrowserInfo.IsGeckoLike )
                FCKTools.AppendBogusBr( eNewBlock ) ;

            oRange.InsertNode( eNewBlock ) ;

            // This is tricky, but to make the new block visible correctly
            // we must select it.
            if ( FCKBrowserInfo.IsIE )
            {
                // Move the selection to the new block.
                oRange.MoveToElementEditStart( eNewBlock ) ;
                oRange.Select() ;
            }

            // Move the selection to the new block.
            oRange.MoveToElementEditStart( bIsStartOfBlock && !bIsEndOfBlock ? eNextBlock : eNewBlock ) ;
        }

        if ( FCKBrowserInfo.IsGeckoLike )
        {
            if ( eNextBlock )
            {
                // If we have split the block, adds a temporary span at the
                // range position and scroll relatively to it.
                var tmpNode = this.Window.document.createElement( 'span' ) ;

                // We need some content for Safari.
                tmpNode.innerHTML = '&nbsp;';

                oRange.InsertNode( tmpNode ) ;
                FCKDomTools.ScrollIntoView( tmpNode, false ) ;
                oRange.DeleteContents() ;
            }
            else
            {
                // We may use the above scroll logic for the new block case
                // too, but it gives some weird result with Opera.
                FCKDomTools.ScrollIntoView( eNextBlock || eNewBlock, false ) ;
            }
        }

        oRange.Select() ;
    }

    // Release the resources used by the range.
    oRange.Release() ;

    return true ;
}

FCKEnterKey.prototype._ExecuteEnterBr = function( blockTag )
{
    // Get the current selection.
    var oRange = new FCKDomRange( this.Window ) ;
    oRange.MoveToSelection() ;

    // The selection boundaries must be in the same "block limit" element.
    if ( oRange.StartBlockLimit == oRange.EndBlockLimit )
    {
        oRange.DeleteContents() ;

        // Get the new selection (it is collapsed at this point).
        oRange.MoveToSelection() ;

        var bIsStartOfBlock    = oRange.CheckStartOfBlock() ;
        var bIsEndOfBlock    = oRange.CheckEndOfBlock() ;

        var sStartBlockTag = oRange.StartBlock ? oRange.StartBlock.tagName.toUpperCase() : '' ;

        var bHasShift = this._HasShift ;
        var bIsPre = false ;

        if ( !bHasShift && sStartBlockTag == 'LI' )
            return this._ExecuteEnterBlock( null, oRange ) ;

        // If we are at the end of a header block.
        if ( !bHasShift && bIsEndOfBlock && (/^H[1-6]$/).test( sStartBlockTag ) )
        {
            // Insert a BR after the current paragraph.
            FCKDomTools.InsertAfterNode( oRange.StartBlock, this.Window.document.createElement( 'br' ) ) ;

            // The space is required by Gecko only to make the cursor blink.
            if ( FCKBrowserInfo.IsGecko )
                FCKDomTools.InsertAfterNode( oRange.StartBlock, this.Window.document.createTextNode( '' ) ) ;

            // IE and Gecko have different behaviors regarding the position.
            oRange.SetStart( oRange.StartBlock.nextSibling, FCKBrowserInfo.IsIE ? 3 : 1 ) ;
        }
        else
        {
            var eLineBreak ;
            bIsPre = sStartBlockTag.IEquals( 'pre' ) ;
            if ( bIsPre )
                eLineBreak = this.Window.document.createTextNode( FCKBrowserInfo.IsIE ? '\r' : '\n' ) ;
            else
                eLineBreak = this.Window.document.createElement( 'br' ) ;

            oRange.InsertNode( eLineBreak ) ;

            // The space is required by Gecko only to make the cursor blink.
            if ( FCKBrowserInfo.IsGecko )
                FCKDomTools.InsertAfterNode( eLineBreak, this.Window.document.createTextNode( '' ) ) ;

            // If we are at the end of a block, we must be sure the bogus node is available in that block.
            if ( bIsEndOfBlock && FCKBrowserInfo.IsGeckoLike )
                FCKTools.AppendBogusBr( eLineBreak.parentNode ) ;

            if ( FCKBrowserInfo.IsIE )
                oRange.SetStart( eLineBreak, 4 ) ;
            else
                oRange.SetStart( eLineBreak.nextSibling, 1 ) ;

            if ( ! FCKBrowserInfo.IsIE )
            {
                var dummy = null ;
                if ( FCKBrowserInfo.IsOpera )
                    dummy = this.Window.document.createElement( 'span' ) ;
                else
                    dummy = this.Window.document.createElement( 'br' ) ;

                eLineBreak.parentNode.insertBefore( dummy, eLineBreak.nextSibling ) ;

                FCKDomTools.ScrollIntoView( dummy, false ) ;

                dummy.parentNode.removeChild( dummy ) ;
            }
        }

        // This collapse guarantees the cursor will be blinking.
        oRange.Collapse( true ) ;

        oRange.Select( bIsPre ) ;
    }

    // Release the resources used by the range.
    oRange.Release() ;

    return true ;
}

// Outdents a LI, maintaining the selection defined on a range.
FCKEnterKey.prototype._OutdentWithSelection = function( li, range )
{
    var oBookmark = range.CreateBookmark() ;

    FCKListHandler.OutdentListItem( li ) ;

    range.MoveToBookmark( oBookmark ) ;
    range.Select() ;
}

// Is all the contents under a node included by a range?
FCKEnterKey.prototype._CheckIsAllContentsIncluded = function( range, node )
{
    var startOk = false ;
    var endOk = false ;

    /*
    FCKDebug.Output( 'sc='+range.StartContainer.nodeName+
            ',so='+range._Range.startOffset+
            ',ec='+range.EndContainer.nodeName+
            ',eo='+range._Range.endOffset ) ;
    */
    if ( range.StartContainer == node || range.StartContainer == node.firstChild )
        startOk = ( range._Range.startOffset == 0 ) ;

    if ( range.EndContainer == node || range.EndContainer == node.lastChild )
    {
        var nodeLength = range.EndContainer.nodeType == 3 ? range.EndContainer.length : range.EndContainer.childNodes.length ;
        endOk = ( range._Range.endOffset == nodeLength ) ;
    }

    return startOk && endOk ;
}

// Kludge for #247
FCKEnterKey.prototype._FixIESelectAllBug = function( range )
{
    var doc = this.Window.document ;
    doc.body.innerHTML = '' ;
    var editBlock ;
    if ( FCKConfig.EnterMode.IEquals( ['div', 'p'] ) )
    {
        editBlock = doc.createElement( FCKConfig.EnterMode ) ;
        doc.body.appendChild( editBlock ) ;
    }
    else
        editBlock = doc.body ;

    range.MoveToNodeContents( editBlock ) ;
    range.Collapse( true ) ;
    range.Select() ;
    range.Release() ;
}
